I'm assuming I could counter offer, but their offer expires in 2 days so I feel like it is rushed and I should pass so I can take more time and do my due diligence on the best approach for selling the property.  

In Kansas, once you begin negotiations with one buyer, you are not allowed to negotiate with another until the latest counter offer has expired. 2) The key is just to find an investor friendly agent.

But, what if you received a reasonable $975k counteroffer on your $1M property?

from what ihave seen here there is not much negotiating room as evidenced by the counter offers we receive 

There are delays in communication, multiple counteroffers, an ever-changing timeline, to name a few.

I have clients shipping from $300k to $1m and all markets are competitive with multiple counter offers often above asking.  

Following 3 counter-offers, we finally agreed on a price of $752,000 with a quicker than expected close date.

They listed it as 2 bed 1 bath in one unit and only 1 bed 1 bath in the other unit, when in reality the two units were mirror images of each other.We went back and forth with offers and counter-offers.

This PM was recommended by another investor.I decided to counter offer for $95K.

yeah the one property i went in on i was projecting to make 500 cashflow it was a triplex but unfortunately couldnt cover the asking price and they shot down my offer and counter offered at their original list pirce.